1. Field of the Invention
The present invention relates to metallurgy and, particularly, the steelmaking arts. Specifically, the present invention provides a tundish, or reservoir vessel, having provisions for collecting hazardous fumes or gases.
2. Description of the Related Art
Tundishes are refractory-lined metal boxes conventionally used as a reservoir to control the flow of liquid metal between metal-working vessels, such as between a ladle and a continuous casting mold. In a typical tundish, metal flows into the vessel, fills it to a certain level, and exits through one or more bottom ports, often referred to as tundish nozzles. Typically, the sidewalls and bottom of a tundish are lined with at least one permanent refractory lining such as brick, and an inner expendable refractory lining which must be replaced periodically.
Refractory linings are known in the art such as described in U.S. Pat. No. 4,012,029 to Seguin et al. Seguin et al. describe a tundish having a refractory lining. The lining is disclosed as a cast monolithic lining. It is preferred to utilize a unitary refractory lining that is replaceable. Accordingly, artisans have directed efforts to such designs such as described in U.S. Pat. No. 4,993,692 to Brown et al. Brown et al. describe a tundish having a rigid outer case, an "inner expendable lining," and a flow control device (apparently integrally formed with the lining). The lining and flow control device are removable from the tundish.
It is also desirable to provide various flow control forms in the tundish or reservoir for manipulating the flow of the molten metal within and from the tundish. Accordingly, artisans have devoted efforts to the design of such flow control forms. U.S. Pat. No. 5,246,209 to Heaslip et al., pertains to a tundish having a flow control wall. FIGS. 2 and 5 of that patent illustrate in greater detail that flow control wall.
Efforts have also been directed toward providing sealed tundishes. U.S. Pat. No. 5,645,121 to Barnes is directed to a sealed tundish. The sealing means is described as a collection of planar rectangular boards arranged in abutting side-by-side relation along the top of the tundish. The boards are formed from a refractory ceramic fiber material. The ceramic fiber boards are used to help retain a blanket of argon gas introduced within the tundish, typically during a preheat operation. These moderately heat resistant ceramic fiber boards are prone to burn up or otherwise degrade upon the tundish reaching its maximum temperature. The boards are not provided to form a sealed tundish having fume collection provisions. Although the use of such planar members might reduce the level of hazardous fumes otherwise emitted from the tundish, there remains a need for significantly improved fume collection from a tundish.
In particular, there is a need for a tundish utilizing a replaceable unitary refractory lining in combination with provisions for improved fume collection from the tundish. It would also be particularly desirable to incorporate flow control provisions within the interior of the tundish, and especially in combination with a replaceable unitary refractory lining and/or improved fume collection provisions.